Focusing on the adaptive immune system makes cancer treatments more difficult to develop due to the specificity of T cells, B cells, antibodies, and their targets. Each cancer type and patient cancer case could potentially need a unique treatment of immunotherapy if manipulating the adaptive immune system. Dr. Maya Saleh, leader of the study published in Immunity and professor at McGill University, describes the more general, possibly quicker action of enabling the immune system to detect and fight cancer: innate immune cells "broadly survey tissues for the presence of 'danger' signals." The key word here is "broadly."
In the study, Saleh and her team looked at experimental and control mice with colorectal cancer to determine the impact of cancer growth and spread. Some mice had impaired immune systems, and results showed that mice with unimpaired immune systems had less cancer growth and spread. Saleh's team was also able to identify specific innate immune cells that were active in preventing cancer growth.
NLRP3, a gene that codes for the production of cryopyrin protein, regulates the innate immune response to injury and invasion and also engages other immune cells (U.S. National Library of Medicine). In their study with colorectal cancer mice, Saleh's team saw NLRP3 act as a sensor that activated an effector cytokine, Interleukin 18. According to the National Center for Biotechnology Information, IL-18 is a proinflammatory cytokine that instigates natural killer (NK) cells activity. Saleh's team found the same action in the mice study. NK cells are innate lymphocytes that recognize abnormal cells (Nature). Cancer cells definitely fit under the definition of "abnormal" - seeing as they grow uncontrollably and irregularly.
Now that this team from McGill University has demonstrated the potential of the innate immune system to target cancer cells and inhibit their growth and spread in the body, the options for therapeutics are many. Harnessing this ability of the innate immune system will be a paramount next step in the fight against cancer.
Check out the following Nature video to hear and see a great overview of current cancer immunotherapies.
Sources: Medical Xpress and McGill University